基于半纤维素定向合成γ-戊内酯的酸碱双功能催化剂的构筑及协同催化性能研究

Efficiently coupling of multiple independent processes between platform chemicals obtained from biomass conversion and their further high value-added transformation is the key technological bottleneck in the field of bio-refinery. Based on the previous research foundation, this proposal aims to synthetize γ-valerolactone based on hemicellulose oriented transformation. During the process of hemicellulose conversion, a series of studies will be conducted according to the cascade reactions such as depolymerization, alcoholysis and hydrogenation etc. By constructing a novel acid-base bifunctional ZrPO@SBA-15 solid catalyst and employing alcohol as the hydrogen donor and solvent, an efficient and green process can be built for γ-valerolactone production using hemicellulose as the raw material under mild conditions. In the process of this proposal implementation, catalysis preparation process will be investigated systematically to determine the change rule of physicochemical properties especially the acid and base properties. Meanwhile, the structure-relationship between the acid-base properties of catalyst and catalytic activities will be studied in detail to discover the acid-base synergistic catalytic mechanism, and the reaction parameters will be optimized to obtain the resulting kinetic parameters in this cascade reactions. Furthermore, the process mechanism will be verified by combining physicochemical properties of catalysts, the acid-base synergistic catalytic mechanism and reaction kinetic parameters. The achievements of this proposal not only provide key reference for developing hemicellulose oriented transformation process, but also lay a foundation for developing catalyst preparation technology.

如何将生物质制备平台化学品及其高附加值转化中多个独立的炼制过程高效耦合是目前生物炼制领域所面临的关键技术瓶颈。基于前期的研究基础，本项目拟以半纤维素定向合成γ-戊内酯为目标，针对转化过程中发生解聚、醇解及加氢等串联反应展开研究，通过构筑新型酸碱双功能ZrPO@SBA-15固体催化剂，利用醇作为质子供体和溶剂，实现温和条件下定向合成γ-戊内酯的绿色工艺过程。项目实施过程中，首先，系统考察催化剂的制备工艺，确定催化剂物理化学性质尤其是酸碱性质的变化规律；其次，深入研究催化剂的酸碱性质与催化活性之间的构效关系，揭示酸碱协同催化机制；接着，优化各反应参数，获悉相应串联反应的动力学参数；最后，结合催化剂的物理化学性质、酸碱协同催化机制和反应动力学参数，阐明半纤维素定向合成γ-戊内酯的过程机制。本项目所获得研究成果不仅为半纤维素定向转化工艺提供了重要的参考，也为发展催化剂制备科学奠定基础。

如何将生物质制备平台化学品及其高附加值转化中多个独立的炼制过程高效耦合是目前生物炼制领域所面临的关键技术瓶颈。本项目以半纤维素定向合成γ-戊内酯为目标，开展了一系列研究：（1）针对糠醛定向合成γ-戊内酯所需催化活性位的类型，开发了ZrPO催化转化糠醛定向合成γ-戊内酯的绿色工艺过程，以ZrPO-1.5为催化剂，以异丙醇为供氢体，在240 oC反应7 h，γ-戊内酯的产率达到67.4%；（2）针对多相催化体系存在的传质传热等限制，开发了温和条件下三氟甲磺酸盐催化转化乙酰丙酸乙酯制备γ-戊内酯的绿色工艺过程，采用Sc(OTf)3为催化剂，以异丙醇为供氢体，在140 oC反应3 h，γ-戊内酯的产率达到92.4%；（3）针对传统加氢过程条件较为苛刻的缺点，开发了TiO2光热协同催化转化糠醛制备糠醛的绿色工艺过程，以乙醇为供氢体，在60 oC反应4.0 h，糠醇的产率为76.2%；（4）通过对光催化反应的应用领域的拓展，开发了非催化光氧化糠醛制备马来酸酐的绿色工艺过程，在1 MPa O2下光照反应8 h，马来酸酐的产率达到了41.5%；（5）通过对锆基催化材料的应用领域的拓展，开发了锆基材料催化转化1,3二羟基丙酮制备乳酸乙酯的绿色工艺过程，以碱式碳酸锆为催化剂，在140 oC下反应4 h，乳酸乙酯的产率达到了85.3%。本项目研究结果隶属于有机化学、材料化学以及化学工程高度交叉，相互渗透的领域，具有重要的研究意义和广泛的应用价值。